. ~/Projects/esp-idf-test/esp-idf/export.sh

on: [push, pull_request]

name: Test

jobs:

  test:

    runs-on: ubuntu-latest

    steps:

      - name: Checkout

        uses: actions/checkout@v2

        with:

          submodules: recursive

      - name: Prepare

        run: sudo apt-get install python-is-python3 gperf -y

      - name: Install

        run: make prepare install

      - name: Build

        run: make build

.idea/

cmake-build-debug/

test/esp-idf

test/tools

test/build

set(srcs

    "esp_osc.c"

    "tinyosc.c"

)

idf_component_register(SRCS ${srcs}

    INCLUDE_DIRS "."

)

MIT License

Copyright (c) 2022 Joël Gähwiler

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all

copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

SOFTWARE.

SHELL := /bin/bash

ESP_IDF_VERSION := "v5.2.2"

fmt:

	clang-format -i ./*.c ./*.h -style="{BasedOnStyle: Google, ColumnLimit: 120, SortIncludes: false}"

	clang-format -i ./test/main/*.c -style="{BasedOnStyle: Google, ColumnLimit: 120, SortIncludes: false}"

prepare:

	git clone --recursive  https://github.com/espressif/esp-idf.git test/esp-idf

	cd test/esp-idf; git fetch; git checkout $(ESP_IDF_VERSION)

	cd test/esp-idf/; git submodule update --recursive --init

update:

	cd test/esp-idf; git fetch; git checkout $(ESP_IDF_VERSION)

	cd test/esp-idf/; git submodule update --recursive --init

install:

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; cd test/esp-idf; ./install.sh esp32

config:

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; . test/esp-idf/export.sh; cd test; idf.py menuconfig

reconfigure:

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; . test/esp-idf/export.sh; cd test; idf.py reconfigure

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; . test/esp-idf/export.sh; cd test; idf.py fullclean

erase:

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; . test/esp-idf/export.sh; cd test; idf.py erase-flash

clean:

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; . test/esp-idf/export.sh; cd test; idf.py clean

build:

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; . test/esp-idf/export.sh; cd test; idf.py build

flash:

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; . test/esp-idf/export.sh;  cd test; idf.py flash

monitor:

	export IDF_TOOLS_PATH=$(shell pwd)/test/tools; . test/esp-idf/export.sh;  cd test; idf.py monitor

simple-monitor:

	@clear

	miniterm.py /dev/cu.SLAB_USBtoUART 115200 --rts 0 --dtr 0 --raw --exit-char 99

run: build flash monitor

# esp-osc

[![Test](https://github.com/256dpi/esp-osc/actions/workflows/test.yml/badge.svg)](https://github.com/256dpi/esp-osc/actions/workflows/test.yml)

[![Release](https://img.shields.io/github/release/256dpi/esp-osc.svg)](https://github.com/256dpi/esp-osc/releases)

**OSC component for esp-idf projects based on the [tinyosc](https://github.com/mhroth/tinyosc) library**

This component bundles the tinyosc library and provides a simple API for sending OSC messages.

## Installation

You can install the component by adding it as a git submodule:

```bash

git submodule add https://github.com/256dpi/esp-osc.git components/esp-osc

git submodule update --init --recursive

```

## Example

An example can be found here: https://github.com/256dpi/esp-osc/blob/master/test/main/main.c.

#include <stdio.h>

#include <stdarg.h>

#include <esp_log.h>

#include "esp_osc.h"

#define TAG "esp-osc"

bool esp_osc_init(esp_osc_client_t *client, uint16_t buf_len, uint16_t port) {

  // free existing memory

  if (client->sbuf != NULL) {

    free(client->sbuf);

  }

  if (client->rbuf != NULL) {

    free(client->rbuf);

  }

  // allocate memory

  client->sbuf = malloc(buf_len);

  client->rbuf = malloc(buf_len);

  client->len = buf_len;

  // close existing socket

  if (client->socket != 0) {

    close(client->socket);

    client->socket = 0;

  }

  // create socket

  client->socket = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);

  if (client->socket <= 0) {

    ESP_LOGE(TAG, "failed to create socket (%d)", errno);

    client->socket = 0;

    return false;

  }

  // bind socket if port is available

  if (port > 0) {

    struct sockaddr_in addr = {0};

    addr.sin_addr.s_addr = inet_addr("0.0.0.0");

    addr.sin_family = AF_INET;

    addr.sin_port = htons(port);

    if (bind(client->socket, (struct sockaddr *)&addr, sizeof(addr)) < 0) {

      ESP_LOGE(TAG, "failed to bind socket (%d)", errno);

      return false;

    }

  }

  return true;

}

esp_osc_target_t esp_osc_target(const char *address, uint16_t port) {

  // prepare target

  esp_osc_target_t target = {0};

  target.addr.sin_addr.s_addr = inet_addr(address);

  target.addr.sin_family = AF_INET;

  target.addr.sin_port = htons(port);

  return target;

}

bool esp_osc_send(esp_osc_client_t *client, esp_osc_target_t *target, const char *topic, const char *format, ...) {

  // send message

  va_list args;

  va_start(args, format);

  bool ret = esp_osc_send_v(client, target, topic, format, args);

  va_end(args);

  return ret;

}

bool esp_osc_send_v(esp_osc_client_t *client, esp_osc_target_t *target, const char *topic, const char *format,

                    va_list args) {

  // prepare message

  uint32_t length = tosc_vwrite((char *)client->sbuf, client->len, topic, format, args);

  // send message

  if (sendto(client->socket, client->sbuf, length, 0, (struct sockaddr *)&target->addr, sizeof(target->addr)) < 0) {

    ESP_LOGE(TAG, "failed to send message (%d)", errno);

    return false;

  }

  return true;

}

bool esp_osc_receive(esp_osc_client_t *client, esp_osc_callback_t callback) {

  // prepare values

  esp_osc_value_t values[32];

  for (;;) {

    // receive message

    ssize_t ret = recvfrom(client->socket, client->rbuf, client->len, 0, NULL, NULL);

    if (ret < 0) {

      ESP_LOGE(TAG, "failed to receive message (%d)", errno);

      return false;

    } else if (ret > client->len) {

      ESP_LOGE(TAG, "discard too long message (%d)", ret);

      return false;

    }

    // check bundle

    if (tosc_isBundle(client->rbuf)) {

      ESP_LOGE(TAG, "discard unsupported bundle");

      return false;

    }

    // parse message

    tosc_message msg = {0};

    int res = tosc_parseMessage(&msg, client->rbuf, client->len);

    if (res < 0) {

      ESP_LOGE(TAG, "failed to parse message (%d)", res);

      return false;

    }

    // get format

    char *fmt = tosc_getFormat(&msg);

    // get size

    size_t size = strlen(fmt);

    if (size > sizeof(values)) {

      ESP_LOGE(TAG, "message has too many values (%d)", size);

      return false;

    }

    // parse values

    for (size_t i = 0; i < size; i++) {

      switch (fmt[i]) {

        case 'i':

          values[i].i = tosc_getNextInt32(&msg);

          break;

        case 'h':

          values[i].h = tosc_getNextInt64(&msg);

          break;

        case 'f':

          values[i].f = tosc_getNextFloat(&msg);

          break;

        case 'd':

          values[i].d = tosc_getNextDouble(&msg);

          break;

        case 's':

          values[i].s = tosc_getNextString(&msg);

          break;

        case 'b':

          tosc_getNextBlob(&msg, &values[i].b, &values[i].bl);

          break;

      }

    }

    // call callback

    if (!callback(tosc_getAddress(&msg), fmt, values)) {

      return false;

    }

  }

  return true;

}

#ifndef ESP_OSC_H

#define ESP_OSC_H

#include <stdbool.h>

#include <stdint.h>

#include <lwip/netdb.h>

#include <tinyosc.h>

#ifdef __cplusplus

extern "C" {

#endif

typedef struct {

  char *sbuf;

  char *rbuf;

  size_t len;

  int socket;

} esp_osc_client_t;

typedef struct {

  struct sockaddr_in addr;

} esp_osc_target_t;

typedef struct {

  union {

    int32_t i;

    int64_t h;

    float f;

    double d;

    const char *s;

    const char *b;

  };

  int bl;

} esp_osc_value_t;

typedef bool (*esp_osc_callback_t)(const char *topic, const char *format, esp_osc_value_t *values);

bool esp_osc_init(esp_osc_client_t *client, uint16_t buf_len, uint16_t port);

esp_osc_target_t esp_osc_target(const char *address, uint16_t port);

bool esp_osc_send(esp_osc_client_t *client, esp_osc_target_t *target, const char *topic, const char *format, ...);

bool esp_osc_send_v(esp_osc_client_t *client, esp_osc_target_t *target, const char *topic, const char *format,

                    va_list args);

bool esp_osc_receive(esp_osc_client_t *client, esp_osc_callback_t callback);

#ifdef __cplusplus

}

#endif

#endif  // ESP_OSC_H

cmake_minimum_required(VERSION 3.5)

include($ENV{IDF_PATH}/tools/cmake/project.cmake)

project(esp-osc)

../../

idf_component_register(SRCS "main.c" INCLUDE_DIRS "")

#include <stdlib.h>

#include <esp_event.h>

#include <esp_log.h>

#include <esp_wifi.h>

#include <nvs_flash.h>

#include <esp_osc.h>

#define WIFI_SSID ""

#define WIFI_PASS ""

#define OSC_ADDRESS ""

#define OSC_PORT 0

#define TAG "main"

esp_osc_client_t client;

static void sender() {

  // select targets

  esp_osc_target_t targets[2] = {

      esp_osc_target("127.0.0.1", 9000),

      esp_osc_target(OSC_ADDRESS, OSC_PORT),

  };

  for (;;) {

    // delay

    vTaskDelay(1000 / portTICK_PERIOD_MS);

    // send messages

    for (size_t i = 0; i < 2; i++) {

      esp_osc_send(&client, &targets[i], "test", "ihfdsb", 42, (int64_t)84, 3.14f, 6.28, "foo", 3, "bar");

    }

  }

}

static bool callback(const char *topic, const char *format, esp_osc_value_t *values) {

  // log message

  ESP_LOGI(TAG, "got message: %s (%s)", topic, format);

  for (size_t i = 0; i < strlen(format); i++) {

    switch (format[i]) {

      case 'i':

        ESP_LOGI(TAG, "==> i: %ld", values[i].i);

        break;

      case 'h':

        ESP_LOGI(TAG, "==> h: %lld", values[i].h);

        break;

      case 'f':

        ESP_LOGI(TAG, "==> f: %f", values[i].f);

        break;

      case 'd':

        ESP_LOGI(TAG, "==> d: %f", values[i].d);

        break;

      case 's':

        ESP_LOGI(TAG, "==> s: %s", values[i].s);

        break;

      case 'b':

        ESP_LOGI(TAG, "==> b: %.*s (%d)", values[i].bl, values[i].b, values[i].bl);

        break;

    }

  }

  return true;

}

static void receiver() {

  for (;;) {

    // receive messages

    esp_osc_receive(&client, callback);

  }

}

static void restarter() {

  for (;;) {

    // delay

    vTaskDelay(5000 / portTICK_PERIOD_MS);

    // restart client

    esp_osc_init(&client, 1024, 9000);

  }

}

static void handler(void *arg, esp_event_base_t base, int32_t id, void *data) {

  if (base == WIFI_EVENT) {

    switch (id) {

      case WIFI_EVENT_STA_START:

        // connect to ap

        ESP_ERROR_CHECK_WITHOUT_ABORT(esp_wifi_connect());

        break;

      case IP_EVENT_STA_GOT_IP:

        break;

      case WIFI_EVENT_STA_DISCONNECTED:

        // reconnect Wi-Fi

        ESP_ERROR_CHECK_WITHOUT_ABORT(esp_wifi_connect());

        break;

      default:

        break;

    }

  }

}

void app_main() {

  // initialize NVS flash

  ESP_ERROR_CHECK(nvs_flash_init());

  // initialize networking

  ESP_ERROR_CHECK(esp_netif_init());

  // create default event loop

  ESP_ERROR_CHECK(esp_event_loop_create_default());

  // enable Wi-Fi

  esp_netif_create_default_wifi_sta();

  // initialize Wi-Fi

  wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();

  ESP_ERROR_CHECK(esp_wifi_init(&cfg));

  // set Wi-Fi storage to ram

  ESP_ERROR_CHECK(esp_wifi_set_storage(WIFI_STORAGE_RAM));

  // set wifi mode

  ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));

  // register event handlers

  ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &handler, NULL, NULL));

  ESP_ERROR_CHECK(esp_event_handler_instance_register(IP_EVENT, IP_EVENT_STA_GOT_IP, &handler, NULL, NULL));

  // prepare Wi-Fi config

  wifi_config_t wifi_config = {.sta = {.ssid = WIFI_SSID, .password = WIFI_PASS}};

  ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));

  ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config));

  // start Wi-Fi

  ESP_ERROR_CHECK(esp_wifi_start());

  // prepare client

  esp_osc_init(&client, 1024, 9000);

  // create tasks

  xTaskCreatePinnedToCore(sender, "sender", 4096, NULL, 10, NULL, 1);

  xTaskCreatePinnedToCore(receiver, "receiver", 4096, NULL, 10, NULL, 1);

  xTaskCreatePinnedToCore(restarter, "restarter", 4096, NULL, 10, NULL, 1);

}

/**

 * Copyright (c) 2015-2018, Martin Roth (mhroth@gmail.com)

 *

 * Permission to use, copy, modify, and/or distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH

 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY

 * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,

 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM

 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR

 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR

 * PERFORMANCE OF THIS SOFTWARE.

 */

#include <stddef.h>

#include <stdarg.h>

#include <string.h>

#include <stdio.h>

#if _WIN32

#include <winsock2.h>

#define tosc_strncpy(_dst, _src, _len) strncpy_s(_dst, _len, _src, _TRUNCATE)

#else

#include <netinet/in.h>

#define tosc_strncpy(_dst, _src, _len) strncpy(_dst, _src, _len)

#endif

#if __unix__ && !__APPLE__

#include <endian.h>

#define htonll(x) htobe64(x)

#define ntohll(x) be64toh(x)

#endif

#include "tinyosc.h"

#define BUNDLE_ID 0x2362756E646C6500L  // "#bundle"

// http://opensoundcontrol.org/spec-1_0

int tosc_parseMessage(tosc_message *o, char *buffer, const int len) {

  // NOTE(mhroth): if there's a comma in the address, that's weird

  int i = 0;

  while (buffer[i] != '\0') ++i;  // find the null-terimated address

  while (buffer[i] != ',') ++i;   // find the comma which starts the format string

  if (i >= len) return -1;        // error while looking for format string

  // format string is null terminated

  o->format = buffer + i + 1;  // format starts after comma

  while (i < len && buffer[i] != '\0') ++i;

  if (i == len) return -2;  // format string not null terminated

  i = (i + 4) & ~0x3;  // advance to the next multiple of 4 after trailing '\0'

  o->marker = buffer + i;

  o->buffer = buffer;

  o->len = len;

  return 0;

}

// check if first eight bytes are '#bundle '

bool tosc_isBundle(const char *buffer) { return ((*(const int64_t *)buffer) == htonll(BUNDLE_ID)); }

void tosc_parseBundle(tosc_bundle *b, char *buffer, const int len) {

  b->buffer = (char *)buffer;

  b->marker = buffer + 16;  // move past '#bundle ' and timetag fields

  b->bufLen = len;

  b->bundleLen = len;

}

uint64_t tosc_getTimetag(tosc_bundle *b) { return ntohll(*((uint64_t *)(b->buffer + 8))); }

uint32_t tosc_getBundleLength(tosc_bundle *b) { return b->bundleLen; }

bool tosc_getNextMessage(tosc_bundle *b, tosc_message *o) {

  if ((b->marker - b->buffer) >= b->bundleLen) return false;

  uint32_t len = (uint32_t)ntohl(*((int32_t *)b->marker));

  tosc_parseMessage(o, b->marker + 4, len);

  b->marker += (4 + len);  // move marker to next bundle element

  return true;

}

char *tosc_getAddress(tosc_message *o) { return o->buffer; }

char *tosc_getFormat(tosc_message *o) { return o->format; }

uint32_t tosc_getLength(tosc_message *o) { return o->len; }

int32_t tosc_getNextInt32(tosc_message *o) {

  // convert from big-endian (network btye order)

  const int32_t i = (int32_t)ntohl(*((uint32_t *)o->marker));

  o->marker += 4;

  return i;

}

int64_t tosc_getNextInt64(tosc_message *o) {

  const int64_t i = (int64_t)ntohll(*((uint64_t *)o->marker));

  o->marker += 8;

  return i;

}

uint64_t tosc_getNextTimetag(tosc_message *o) { return (uint64_t)tosc_getNextInt64(o); }

float tosc_getNextFloat(tosc_message *o) {

  // convert from big-endian (network btye order)

  const uint32_t i = ntohl(*((uint32_t *)o->marker));

  o->marker += 4;

  return *((float *)(&i));

}

double tosc_getNextDouble(tosc_message *o) {

  const uint64_t i = ntohll(*((uint64_t *)o->marker));

  o->marker += 8;

  return *((double *)(&i));

}

const char *tosc_getNextString(tosc_message *o) {

  int i = (int)strlen(o->marker);

  if (o->marker + i >= o->buffer + o->len) return NULL;

  const char *s = o->marker;

  i = (i + 4) & ~0x3;  // advance to next multiple of 4 after trailing '\0'

  o->marker += i;

  return s;

}

void tosc_getNextBlob(tosc_message *o, const char **buffer, int *len) {

  int i = (int)ntohl(*((uint32_t *)o->marker));  // get the blob length

  if (o->marker + 4 + i <= o->buffer + o->len) {

    *len = i;  // length of blob

    *buffer = o->marker + 4;

    i = (i + 7) & ~0x3;

    o->marker += i;

  } else {

    *len = 0;

    *buffer = NULL;

  }

}

unsigned char *tosc_getNextMidi(tosc_message *o) {

  unsigned char *m = (unsigned char *)o->marker;

  o->marker += 4;

  return m;

}

tosc_message *tosc_reset(tosc_message *o) {

  int i = 0;

  while (o->format[i] != '\0') ++i;

  i = (i + 4) & ~0x3;             // advance to the next multiple of 4 after trailing '\0'

  o->marker = o->format + i - 1;  // -1 to account for ',' format prefix

  return o;

}

void tosc_writeBundle(tosc_bundle *b, uint64_t timetag, char *buffer, const int len) {

  *((uint64_t *)buffer) = htonll(BUNDLE_ID);

  *((uint64_t *)(buffer + 8)) = htonll(timetag);

  b->buffer = buffer;

  b->marker = buffer + 16;

  b->bufLen = len;

  b->bundleLen = 16;

}

// always writes a multiple of 4 bytes

uint32_t tosc_vwrite(char *buffer, const int len, const char *address, const char *format, va_list ap) {

  memset(buffer, 0, len);  // clear the buffer

  uint32_t i = (uint32_t)strlen(address);

  if (address == NULL || i >= len) return -1;

  tosc_strncpy(buffer, address, len);

  i = (i + 4) & ~0x3;

  buffer[i++] = ',';

  int s_len = (int)strlen(format);

  if (format == NULL || (i + s_len) >= len) return -2;

  tosc_strncpy(buffer + i, format, len - i - s_len);

  i = (i + 4 + s_len) & ~0x3;

  for (int j = 0; format[j] != '\0'; ++j) {

    switch (format[j]) {

      case 'b': {

        const uint32_t n = (uint32_t)va_arg(ap, int);  // length of blob

        if (i + 4 + n > len) return -3;

        char *b = (char *)va_arg(ap, void *);  // pointer to binary data

        *((uint32_t *)(buffer + i)) = htonl(n);

        i += 4;

        memcpy(buffer + i, b, n);

        i = (i + 3 + n) & ~0x3;

        break;

      }

      case 'f': {

        if (i + 4 > len) return -3;

        const float f = (float)va_arg(ap, double);

        *((uint32_t *)(buffer + i)) = htonl(*((uint32_t *)&f));

        i += 4;

        break;

      }

      case 'd': {

        if (i + 8 > len) return -3;

        const double f = (double)va_arg(ap, double);

        *((uint64_t *)(buffer + i)) = htonll(*((uint64_t *)&f));

        i += 8;

        break;

      }

      case 'i': {

        if (i + 4 > len) return -3;

        const uint32_t k = (uint32_t)va_arg(ap, int);

        *((uint32_t *)(buffer + i)) = htonl(k);

        i += 4;

        break;

      }

      case 'm': {

        if (i + 4 > len) return -3;

        const unsigned char *const k = (unsigned char *)va_arg(ap, void *);

        memcpy(buffer + i, k, 4);

        i += 4;

        break;

      }

      case 't':

      case 'h': {

        if (i + 8 > len) return -3;

        const uint64_t k = (uint64_t)va_arg(ap, long long);

        *((uint64_t *)(buffer + i)) = htonll(k);

        i += 8;

        break;

      }

      case 's': {

        const char *str = (const char *)va_arg(ap, void *);

        s_len = (int)strlen(str);

        if (i + s_len >= len) return -3;

        tosc_strncpy(buffer + i, str, len - i - s_len);

        i = (i + 4 + s_len) & ~0x3;

        break;

      }

      case 'T':  // true

      case 'F':  // false

      case 'N':  // nil

      case 'I':  // infinitum

        break;

      default:

        return -4;  // unknown type

    }

  }

  return i;  // return the total number of bytes written

}

uint32_t tosc_writeNextMessage(tosc_bundle *b, const char *address, const char *format, ...) {

  va_list ap;

  va_start(ap, format);

  if (b->bundleLen >= b->bufLen) return 0;

  const uint32_t i = tosc_vwrite(b->marker + 4, b->bufLen - b->bundleLen - 4, address, format, ap);

  va_end(ap);

  *((uint32_t *)b->marker) = htonl(i);  // write the length of the message

  b->marker += (4 + i);

  b->bundleLen += (4 + i);

  return i;

}

uint32_t tosc_writeMessage(char *buffer, const int len, const char *address, const char *format, ...) {

  va_list ap;

  va_start(ap, format);

  const uint32_t i = tosc_vwrite(buffer, len, address, format, ap);

  va_end(ap);

  return i;  // return the total number of bytes written

}

void tosc_printOscBuffer(char *buffer, const int len) {

  // parse the buffer contents (the raw OSC bytes)

  // a return value of 0 indicates no error

  tosc_message m;

  const int err = tosc_parseMessage(&m, buffer, len);

  if (err == 0)

    tosc_printMessage(&m);

  else

    printf("Error while reading OSC buffer: %i\n", err);

}

void tosc_printMessage(tosc_message *osc) {

  printf("[%lu bytes] %s %s",

         osc->len,              // the number of bytes in the OSC message

         tosc_getAddress(osc),  // the OSC address string, e.g. "/button1"

         tosc_getFormat(osc));  // the OSC format string, e.g. "f"

  for (int i = 0; osc->format[i] != '\0'; i++) {

    switch (osc->format[i]) {

      case 'b': {

        const char *b = NULL;  // will point to binary data

        int n = 0;             // takes the length of the blob

        tosc_getNextBlob(osc, &b, &n);

        printf(" [%i]", n);                                       // print length of blob

        for (int j = 0; j < n; ++j) printf("%02X", b[j] & 0xFF);  // print blob bytes

        break;

      }

      case 'm': {

        unsigned char *m = tosc_getNextMidi(osc);

        printf(" 0x%02X%02X%02X%02X", m[0], m[1], m[2], m[3]);

        break;

      }

      case 'f':

        printf(" %g", tosc_getNextFloat(osc));

        break;

      case 'd':

        printf(" %g", tosc_getNextDouble(osc));

        break;

      case 'i':

        printf(" %ld", tosc_getNextInt32(osc));

        break;

      case 'h':

        printf(" %lld", tosc_getNextInt64(osc));

        break;

      case 't':

        printf(" %lld", tosc_getNextTimetag(osc));

        break;

      case 's':

        printf(" %s", tosc_getNextString(osc));

        break;

      case 'F':

        printf(" false");

        break;

      case 'I':

        printf(" inf");

        break;

      case 'N':

        printf(" nil");

        break;